Leaking oil seal.

[Crusty Snippets]

The oil seal at the forward end of the drive shaft, in the 90 degree gear case is leaking. My manual has nothing to say about this. But another XS11 owner told me how to remove.
Have the gear case on the bench. Oil seal will get destroyed by the time I get it out.
Anyone know the part number for the seal?
Is there an online parts diagram or list I can use?
Have been doing some searching, but so far no luck. My bike is a 79 Special. Spare is an 81 MNS.

Thank you. Crusty Snippets.

[DiverRay]

The middle and final drive units are in a different manual. I know there is one here, just don't remember where. For the seal, look up the part on the Yamaha site. Part number should have the seal size as part of it.
boats.net site: http://www.boats.net/parts/search/Ya...EAR/parts.html #21 is the seal.

[crazy steve]

Catatonic Bug has the drive manual in download form on his site...

[Crusty Snippets]

Seal

The middle and final drive units are in a different manual. #21 is the seal.

Sweet. That is the one. I was on their site but could not find it. They have the seal, but not the inner gasket.
I will try my local bearing shop for the seal. If no go will order it from the site you linked.

Thank you. Unkle Crusty*

[3Phase]

Be Careful!

I hate to say it but you'd be better off just buying another middle drive that doesn't leak.

Changing the output shaft seal on the middle drive is not a trivial job and there's a crush washer that has to be replaced. From the same boats.net page:
Item #16 2H7-17571-01-00 SPACER, EXPANSION

If the output shaft is too loose then it'll slowly wobble itself to death or break a tooth off one of the gears; too tight and it'll probably seize at whatever-speed.

Yes, you can ride a slide until the bike stops, just ask Diver Ray, but it's one of the more exciting things I've seen anyone do at ~70MPH.

.

[Bergman16]

middle drive from a 78 just popped up on ebay, not sure it's the right fitment/useful but might be worth a look:

http://www.ebay.com/itm/1978-Yamaha-...5d81db&vxp=mtr

[DiverRay]

ANY XS1100 middle drive will work. As Crusty is in BC, he should probably check for something in Canada before going for the import taxes/time lost. Also, Andreashweiss is close to him, and has a good middle drive available.

[Crusty Snippets]

Gear case.

I have an 81 MNS with 28000 K on it. Andre does have a unit.
Any reason the washer has to be replaced. I am working outside of it.
The bearing, O ring and washer are all contained in the alloy housing piece.
Changing the outer seal should not change anything further in. that is also a question. I assumed the leak was from the outer seal, not the O ring. If the O ring was leaking, the seal should have stopped any oil going further. The bearings all sound good running dry after washing.

Any thoughts on where I can find the large inner gasket, other than the Yami dealer? Or do I just make one.

Thank you all for the input so far.

Unkle Crusty*

[bikerphil]

Any reason the washer has to be replaced.

It is not an ordinary washer, it is a crush collar. It collapses to a certain depth when the proper torque is applied to the end nut, which you will need to remove to get to the seal. As was mentioned, too loose or too tight could result in a catastrophic failure.

[3Phase]

The straight dope

I have an 81 MNS with 28000 K on it. Andre does have a unit.

That's almost new, I'd get it in a heartbeat.

Any reason the washer has to be replaced. I am working outside of it.

Well, if you have to ask ....

As Phil mentioned, the crush washer is a one-time use disposable spacer. If you try to re-use the washer you should at least "know what you are doing! (TM)" because you will need either a very expensive in/lb torque wrench or a very finely calibrated wrist that you obtained through experience -- preferably both. Full stop.

Even then it's not guaranteed because there although there is a gear lash min/max limit listed, there's no specification anywhere in the fine manual for setting up the middle drive on the XS1100. The PDF manual that's available is for the XS750 so it will get you close because the XS750/850/1100 all use the same middle drive but how close? I have no idea and neither does anyone else.

Basically, instead of measuring 60 times to make up the correct stack of shims to set the bearing preload, Yamaha decided to use a crush washer. It's supposed to collapse down as the giant lock nut is torqued down to set the bearing preload on the output shaft. To a lesser extent it also sets the last smidgen of adjustment of the output shaft depth and the gear face heel/toe contact pattern. Have you ever painted up a set of gears? Now's your chance!

So, yes you can re-use the crush washer but you should not re-use it even if you "know what your doing! (TM)"

It's up to you but I'd just buy another middle drive that's already set up from the factory and doesn't leak.

The bearing, O ring and washer are all contained in the alloy housing piece.
Changing the outer seal should not change anything further in. that is also a question. I assumed the leak was from the outer seal, not the O ring. If the O ring was leaking, the seal should have stopped any oil going further. The bearings all sound good running dry after washing.

Any thoughts on where I can find the large inner gasket, other than the Yami dealer? Or do I just make one.

Thank you all for the input so far.

Unkle Crusty*

The output shaft seal keeps oil from seeping out around drive flange on the output shaft.

The o-ring should be alright and it keeps oil from seeping out between the pinion shim stack and the bearing housing.

You can buy a new inner gasket 1J7-17518-00-00 or make one. They've been discontinued but there are still plenty of them on the 'net and I bought bag of them a couple of years ago. I used them up with different projects here and there but I'd do it again.

.

[Crusty Snippets]

Got it.

Some days things are not as simple as they first appear.
Thank you 3Phase and bikerphil.
The nut was on fairly snug. Would be interesting to read a proper work shop manual, on how to set up that crush washer. There are two brass shims as part of the original setup.
I will take a good look at my spare. It is black. Think anyone will notice.
If it is no good I will contact Andre. I think he is in Osoyoos, which is about 200 miles inland from here.

Unkle Crusty*

[Crusty Snippets]

Gear case

Two guys on my Island know how to set bevel gears. One a mechanic, and one a machinist. The spare middle drive is in Yami. Have a new seal, waiting for the crush washer. Probably get new bearings too. Not in a rush to work on it. Have a no go situation at the moment.
Also inherited another XS1100 that has not run for a few years.

Unkle Crusty*

[3Phase]

Roight on!

New bearings are going to be more than a little spendy but when it's set up it'll last for a while.

.

[Crusty Snippets]

Bearings

I have been busy working on my boat for the last month. 1 1/2 weeks to go. Then I can study the no go electrical problem, and have a good look at the bearings. Yami, when the side car is attached, is my truck, which I need to fetch propane and other things.
Crush washer arrived at the local Yamaha dealer.
Going to look at my next XS1100 on Saturday. Found out today, I can have a hauling trailer as well.

Unkle Crusty